#include <stdio.h>
#include <ctype.h>
#include <string.h>


int main(int argc, char *arv[]) {
    char action = 'p';
    if (argc > 1) {
        if (!strncmp(arv[1],"-u",2)){
            action = 'u';
        } else if (!strncmp(arv[1],"-l",2)){
            action = 'l';
        }
    }
    char c;
    while ((c = getchar()) != EOF) {
        switch (action) {
            case 'p':
                putchar(c);
                break;
            case 'u':
                putchar(toupper(c));
                break;
            case 'l':
                putchar(tolower(c));
                break;
        }
    }
    return 0;
}